A voltage regulator provides a regulated output voltage. For example, a voltage regulator can receive a voltage from a potentially unstable power supply and output a substantially constant lower voltage, which is useful for, e.g., digital circuits requiring a substantially constant voltage. In systems on a chip, the current drawn by the voltage regulator can become a significant contributor to the total power drawn by the chip in a power saving mode. Even though the core logic may not be operating in a power saving mode, the voltage regulator continues to draw current, and may be needed by certain components that continue operating in a power saving mode.